Lucene 6.2 introduces the new `Analyzer.normalize` API, which allows to apply
only character-level normalization such as lowercasing or accent folding, which
is exactly what is needed to process queries that operate on partial terms such
as `prefix`, `wildcard` or `fuzzy` queries. As a consequence, the
`lowercase_expanded_terms` option is not necessary anymore. Furthermore, the
`locale` option was only needed in order to know how to perform the lowercasing,
so this one can be removed as well.
Closes#9978
This commit makes queries and filters parsed the same way using the
QueryParser abstraction. This allowed to remove duplicate code that we had
for similar queries/filters such as `range`, `prefix` or `term`.